I put together a gif with some example content from Leap when I posted Leap on Product Hunt. You can check it out here if you like: https://www.producthunt.com/posts/leap-by-yc. I'd describe it as a hybrid. I'd love to hear which bucket you'd put it in.
>>cbcowa+(OP)
Not OP but to me it looks like a Reddit clone with a few more "fun features" with the emojis. It could very well be based off of reddit considering it's open source.
>>autotu+gk
I find it interesting that the reply button in the stream/index is so prominent. I'd view that as too dominant a design decision, but then perhaps fostering discussion/involvement at the cost of style or following an off-site link is worth the trade off.
>>cbcowa+(OP)
Not a whole lot to go on - what does it look like once comments are posts?
But it looks like your topic discovery is "feed" style, although that could (I can't tell) lead into branching discussions (Reddit/HN) or sequential (FB/forums)